• Journal of Korean Society for Atmospheric Environment
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• v.13 no.3
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• pp.207-214
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• 1997

We collected airborne complex mixtures in a industrial area of Yeochun, and examined whether these complex mixtures could affect gap junctional intercellular communication (GJIC) in a cultured WBF-344 rat liver epithelial cells (LEC). Since the reduction of GJIC plays an important role in chemical carcinogenesis, measurement of changes of GJIC is a meaningful method to screen carcinogenicity of these mixtures. High and low volume samples were dissolved in dimethyl sulfoxide (DMSO) and tested. Blank filter extractions were also examined for exclud-ing possible toxicity of filter itself, and TPA (12-O-tetradecanoylphorbol-13-acetate) and DMSO were used as positive and negative control, respectively. When the cells were exposed to samples at concentration below that required to maintain rather than 85% cell viability based on the result of neutral red uptake assay, maximal inhibition of GJIC was observed at 1hr after treatment with both high and low volume samples by scrape-loading dye transfer assay. In fluorescence recovery after photobleaching assay, recovery rates via gap junctions were 33%/min in high volume sample and 62%/min in low volume sample. In together, airborne samples collected in Yeochun inhibited GJIC in a cultured WBF-344 rat LEC. These results suggest airborne samples tested in this experiment may attribute to cause a certain type and degree of cancers in in vivo when exposured for some periods.

• KIEE International Transactions on Electrophysics and Applications
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• v.12C no.4
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• pp.229-235
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• 2002

The apparent volume resistivity of powders measured by both the tapping and the compressing methods was compared in this study. Factors such as applied voltage, pressure, corona charging, and so on affecting the apparent volume resistivity of polymer powders were also examined experimentally. Powders of polyacrylonitrile and Nylon 11 were mainly used. The values of the apparent resistivity of polymer powders taken by the tapping method turned out to be larger than those taken by the compressing method, which indicates that the apparent volume resistivity of polymer powders depends strongly on the measurement method. The apparent resistivity of polymer powders increased with an increase in applied voltage while it decreased with an increase in pressure, tapping time, and particle size. The influence of the moisture content of powder and corona charging on the resistivity of polymer powders is also discussed.

• Journal of the Korean Society of Physical Medicine
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• v.7 no.2
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• pp.157-164
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• 2012

Purpose : The Purpose of this study was on determine whether thoracic expension exercise might increase the pulmonary function of the patients with stroke. Methods : Fourty paients with stroke were randomly assigned to experimental(n=20) and control group(n=20). During four weeks, each group participated thirty minutes for five times per week. Subjects were assessed using pre-value and post-value measurement pulmonary function(Forced vital capacity, Forced expiratory volume at one second, FEV1/FVC, Peak expiratory flow, Tidal volume, vital capacity, Inspiratory capacity, Expiratory reserve volume, Inspiratory reserve volume). Results : These finding suggest that experimental group was significant increase in FVC, FEV1, PEF, TV, IC, IRV, ERV($p$<.05). In comparison of two group, experimental group was high pulmonary function than control group. Conclusion : This study showed experimental group can be used to improve pulmonary function than control group. Thus it indicates that the thoracic expension exercise will be more improved through the continued respiratory exercise program.

• Korean Chemical Engineering Research
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• v.43 no.5
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• pp.637-640
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• 2005

The density of polar-nonpolar liquid mixtures composed of methyl tert-butyl ether(MTBE) and 2,2,4-trimethylpentane, and methyl ethyl ketone (MEK) and 2,2,4-trimethylpentane, and the density of polar-polar liquid mixture of MTBE and MEK were measured by densitometer at 278.15 K, 288.15 K and 298.15 K, respectively. The excess molar volume of the binary systems calculated from the measured density was shown good agreement with the calculated one by the cubic Peng-Robinson- Stryjek-Vera (PRSV) equation of state together with Huron-Vidal mixing rule and it confirmed that the cubic PRSV equation of state could be used in the molar volume calculation of polar mixture.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.455-458
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• 2002

In this paper, the physical and volume resistivity properties of cross-linked polyethylene (XLPE) for ultra-high voltage investigated due to temperature dependence, and the measurement of volume resistivity used to highmegohm meter is measured from 1 to 30 minutes when the each applied voltage, for example, DC 100[V], 250[V], 500[V] and 1000[V] is applied, according to the step voltage application method. From FT-IR spectrum as an analysis of physical properties, a strong absorption in wavenumbers 700 to 730[$cm^{-1}$ /], 1456[$cm^{-1}$ /] and 2700 to 3000 [$cm^{-1}$ /] observed by the methyl groups(CH$_2$). From the analysis of DSC, the crystalline melting points of the specimen observed in the temperature 60[$^{\circ}C$] and 106.58[$^{\circ}C$].

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.2
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• pp.119-125
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• 2013

In this paper, semiconducting shield specimens for a DC cable is fabricated and characterized by measurement of volume resistance, tensile strength, and the coefficient of expansion to show the electrical and mechanical characteristics of the semiconducting shield. Due to the PTC phenomenon, the volume resistance at $25^{\circ}C$ increases rapidly in comparison to the volume resistance at $90^{\circ}C$. Since the compounding ratio of carbon black is low, the tensile strength and density become lower and the coefficient of expansion is increased. As the general specification of the tensile strength and density is $0.8kgf/mm^2$ and 150%, respectively, the fabricated specimen in this paper has excellent mechanical characteristic.

• Journal of Sensor Science and Technology
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• v.17 no.1
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• pp.81-85
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• 2008

This paper addressed real-time urine monitoring device for intensive care patients. The device was developed to detect and count each urine drop using optical sensor and calculate the current urine output volume and its hourly rate. In experiment, the water volume scale of drainage bottle was observed and compared with the count of the device so that the volume of each drop was found to vary with the dropping rate per minute. From this measurement, the relationship equation was derived to estimate the total water volume from the drop rate (correlation coefficient : r= 0.99). The developed device could be applied to count patient's urine drop successfully. Therefore, this device can be used to monitor intensive care patient's urine status in real-time.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.270-272
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• 1997

In order to a study on the electrical properties of silicone gel due to the curing condition, the volume resistivity test is researched. For experiment, we have made up several samples of different curing temperature and time such as 1[H], 2[H] at 125[$^{\circ}C$], 150[$^{\circ}C$], 160[$^{\circ}C$], 170[$^{\circ}C$], 180[$^{\circ}C$]. A measurement of volume resistivity using the VMG-1000 highmegohm meter is recorded after 10 minutes when the each voltage, and DC 500[V] and 1000[V] is applied. A coaxial cylindrical liquid electrode to measure volume resistivity of specimen is used, and its geometric capacitance is 2[pF]. As a result of the experiment, the electrical properties of specimen cured at 170[$^{\circ}C$] for 2[H] is superior.

• Journal of The Korean Society of Integrative Medicine
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• v.4 no.4
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• pp.13-19
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• 2016

PURPOSE : The purpose of this study was to determine whether tredmill exercise increases pulmonary function and decreases body mass index of the 20s obesity. METHOD : Thirty obesity in their 20s were randomly assigned to on experimental group (n=15) or control group (n=15). Over the course of four weeks, the experimental group participated in tredmill exercise for 30 minutes three times per week and the control group participated in auto-med exercise for 30 minutes three times per week. Subjects were assessed pre-test and post-test by measurement of pulmonary function (tidal volume, inspiration reserve volume, expiratory reserve volume, vital capacity) and body mass index. RESULT : Our findings show that the experimental group had significant difference in expiratory reserve volume and vital capacity and body mass index (p<.05). In the comparison of the two groups, the experimental group had higher pulmonary function and lower body mass index than the control group. CONCLUSION : In this study, the experimental group showed greater improvement in pulmonary function than the control group, which indicates that the tredmill exercise is effective at increasing the pulmonary function and body mass index 20s obesity.

• The Korean Journal of Nuclear Medicine
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• v.17 no.1
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• pp.55-62
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• 1983

In 16 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography(ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-me an-square error of less than 2% between duplicate measurements in 16 individuals. The volume measurements were validated by the use of phantoms.